Swivel joint



Patented May 7, 1946 SWIVEL JOINT Dwight M. Phillips,'Fullerton, Calif., assignor to Chiksan Tool Company, Brea, Calif., a corporation of California Application April 21, 1942, Serial No. 439,849

3 Claims.

This invention relates to rotatable connections or swivel joints and relates more particularly to fiuid conducting swivel joints. A general object of this invention is to provide a practical, effective fluid conducting swivel joint capable of transmitting electrical current when in operation.

Another object of this invention is to provide a -iiuid conducting swivel joint embodying novel means for uninterruptedly transmitting electrical current between the body sections of the joint when there is high speed or low speed relative rotation between the sections.

Another object of this invention is to provide a swivel joint of the character mentioned in which the current transmitting means offers a minimum of resistance to relative rotation be.- tween the sections, develops a minimum of heat y and is long wearing.

. without disturbing the bearing.

The various objects and features of my invention will Foe'fully understood from the following detailed description of a typical preferred form and application of my invention, throughout which description reference is made to the accompanying drawing, in which:

Fig. 1 is a side elevation of the joint provided by this invention with a portion broken away to illustrate the main parts in longitudinal cross section and Fig. 2 is an end view of the joint with a portion broken away to show the principal parts in transverse cross section.

The swivel joint provided by this invention may be said to comprise, generally, two tubular sections A and B arranged in telescopic relation, an anti-friction-bearing III-connecting the sections A and B for free relative rotation, sealing means.

II for preventing the leakage of fluid from between the sections A and B'and means I2 for I conducting an electrical current from one section4 to the other.

The two sections A and Bare adapted to be applied or secured to relatively rotating parts of a fluid line, or the like. l'I'he sections A and B are engaged or telescoped one within the other, the

section A being the inner section and the section B being the outer section. It is to be understood that the sections A and B may be varied somewhat in shape and construction depending upon the character of the fluid line and the manner in which the sections are to be secured in the line. l

In the case illustrated the inner section A is an elongate tubular element of uniform internal diameter engaged on a pipe or tubing T so that the end of the tubing is substantially ush with the inner end of the section A. This provides'for a uniform uninterrupted fluid passage through the section A. An annular seam I2 of soldering, welding or brazing at the outer end of the section A secures the section to the tubing T and provides a fluid seal between the section and the tubing. An annular radially projecting flange I3 is provided onthe exterior of the section A and is spaced between the opposite ends of the section. The external surfaces of the section A and the periphery of the flange I3 are cylindrical and concentric with'the longitudinal axis of the joint. It will be observed that the section A is a simple one piece member.

The section B is a twopiece element compris,.l

ing a coupling nipple Il to be secured to a pipe or tubing T and a coupling or housing member I5.

The coupling nipple Il has an end portion I6 tting around the tubing T and secured and sealed to the tubing by a bead I1 of welding, brazing or soldering. The nipple Il is stepped outwardly or enlarged in' diameter by steps to surround the inner end portion of the section A with substantial clearance. The interior of the nipple Il is designed to house or contain the sealing means II and the electrical conducting means I2. The interior of the nipple I4 has an inwardly facing or axially facing annular shoulder I8 and a second internal annular shoulder I9 facing inthe same direction as and spaced inwardly or axially from the first shoulder I8. The internal wall of the nipple Il between the shoulders I8 and I9 is cylindrical and the internal wall which extends from the shoulder I9 to the inner end of the nipple I I is likewise cylindrical.

The housing member I5 of the section B is a cup-like part having an 4end wall 20 which occu. pies a plane normal to the longitudinal axis of the joint and a main wall or cylindrical tubular wall spaced outwardly from the section A and receiving the large end portion of the nipple I4. An annular groove in the inner edge of the wall 20 carries a grease retainer 2i of felt, or the like, which seals with the external surface of the section A. A raised annular seat 22 is provided on the internal surface of the end wall 20 adjacent its point of connection with the cylindrical main wall of the member I5. The forward or open end of the cuplike member I5 is detachably secured to the nipple I4 by threads 23. A lock ring 24 is set in an annular groove in the member I5 and has an inturned end part 25 passed through an opening 26 in the wall of the member I5 and engaged in a notch 21 in the nipple I4 toprevent unthreading of the nipple and member I5. There is a plurality of spaced openings 2S and a plurality of spaced notches 21 so related that there is an opening 28 in register with a notch 21 regardless oi the rotative position the member I5 may assume when threaded on the nipple I4. This is important in securely clamping the bearing I in place as will be later described.

The bearing IIJ serves to connect the sections A and B for free relative rotation. The bearing I0 surrounds or is engaged on the section A and is housed or received within the member I of the section B. In the preferred construction the bearing I0 is a suitable ball bearing embodying inner and outer races and a series of balls engaged between the races. Seals or lubricant retainers 28 engage between the races of the bearing I0 at opposite sides of the balls to retain lubricant in the bearing so that it is self-lubricating. The inner race of the bearing I0 may directly engage on the periphery of the section A and may have its inner end in direct engagement with the flange I3. is engaged in an annular groove in the section A and cooperates with the outer end of the inner bearing race. The ring 29 acts as a safety element to retain the bearing I0 in the correct position on the section A. The outer end of the outer bearing race bears on the above described seat 22 of the member I5 and the periphery of the outer race may directly engage with the internal surface of the member I5.

A thrust member or spacer 30 is engaged between the nipple I4 and the bearing I0. The spacer 30 is positioned within the cup-like member I5 to lie in substantially the same plane as the flange I3. The inner end of the threaded nipple I4 clamps against the spacer 30 and the spacer 3U in turn clamps against the end of the outer bearing race so that the bearing is held against the seat 22. A grease retainer 3| of felt, or other suitable material, is arranged in an annular groove in the spacer 30 to seal with the periphery of the iiange I3. It will be observed that the bearing I0 is housed where it is entirely protected from external foreign matter, the grease retainers 2I and 3I serving to prevent dust and foreign matter from reaching the bearing.

The sealing means II serves to prevent the leakage of fluid under pressure from between the sections A and B. The means I I is housed Within the nipple I4 and seals with the inner end portion of the section A. In accordance with the broader aspects of the invention the sealing means II may comprise any selected or required type of sealing assembly. In the drawing I have shown a self-lubricating sealing unit comprising a carrier or cage 32. The cage 32 is an annular member of channel shape cross section which Iseats within the nipple I4 to have one end bear against the shoulder I8 and to have the other end lie in the same plane as the shoulder I9. Two spaced sealing rings 33 and 34 are carried in the cage 32 to seal With the peripheral surface of the section A. The ring 33 has a tapering active part A Spring lock ring 29 sloping or pitched through its engagement with the surface of the section A, while the ring 34 is L-shaped in transverse cross section and has an inner ange which conforms to the periphery of the section A. .The cage 32 carries spacers for the rings 33 and 34 and may contain lubricant for the sealing rings. It should be observed that the sealing means Il occurs adjacent the space or gap .35 which is left between the ends of the tubes T and T and between the inner end of the section A and the nipple I4. The sealing means Il is positioned so it prevents the fluid under pressure in the line from reaching the means I2 and the vmiti-friction bearing means Iii.

The means I2 is a feature of the invention, operating to maintain a full adequate and uninterrupted path for the transmission of electrical current between the sections A and B at all times. The electrical conducting means I2 is housed or contained in the nipple III of the section B and includes a cage or carrier 36. The

the nipple I4 and held between the shoulder I9 and the spacer 30, having one side bearing on the l shoulder I9 and having its other side bearing on or engaged by the spacer 30. The carrier 3E may form an abutment for the inner end of the cage 32 of the sealing means I I and thus may serve to hold the sealing means II in the operative position. The periphery of the carrier 36 engages with the interior of the nipple I4, while the internal surface of the carrier 36 is spaced from and clear of the section A. The inner side of the carrier 36, that is, the side which opposes the spacer 30 has a plurality of circumferentially spaced radial grooves or slots 31. The slots 31 have straight flat walls and are preferably of uniform size and shape.

The means I2 further includes blocks or brushes 38 of conducting material arranged in the slots 31 to contact the section A. The number of brushes 38'employed may vary in different forms and applications of the invention. I

have found it practical to employ two diametrically opposite brushes 38 and Where more than two slots 31 are present, the excess slots may remain unoccupied. The brushes 38 are prefer erably carbon brushes proportioned to shiftably or slidably t the slots 31 and their inner faces `are cylindrically concaved to evenly bear on the periphery of the section A. The brushes 38 are guided for radial movement or advancement by the walls of the slots 31 and the side face of the spacer 3D. It will be observed from an inspection of Fig. 1 that the brushes I2 are spaced from and clear of the iiange I3 of the section A but slidably ride on the side face of the spacer 30. 'Ihe brushes 38 are spring held or spring urged to maintain their correct engagement with the section A. Follower plates 39 of metal or other rigid material are arranged against the outer ends of the brushes 38. Springs 40 are arranged under compression between the follower plates 30 and the internal surface of the nipple I4. The springs 40 urge the brushes 38 inwardly into contact with the periphery of the section A and compensate for the Wear of the brushes by advancing the brushes as the wear progresses. The spaced carbon brushes 38 provide an ample electrical connection between the sections A and B and this connection is continuous or uninterrupted during relative rotation between the joint sections. 'Ihe sealing means II prevents the fluid from the line from. reaching the carbon brushes I2, while the grease retainer 3| serves to prevent dust from the carbon brushes from reaching the anti-friction bearing i0.

It is believed that the utility and practicability of the coupling provided by this invention will be readily apparent from the foregoing detailed description. During operation fluid under pressure may be conducted through the tubes T and T' and the sealing means Il effectively prevents the-.escape of the duid pressure from between the sections A and B.- The anti-friction bearing I connects the sections A and B for relative rotation and assures a minimum of friction. The bearing Il is self-lubricating and is fully pro tected so that it is long wearing. The carbon brushes l0 provide for the direct transmission `of electrical current from one section A or B to the other and are springurged to maintain a complete electrical connection between the two sections at all times. In the event the sealing -means Il or the means I2, or both, require repair or replacement the member i5 is unthreaded from the nipple Il. Preparatory to this opera.-

sections ior free relative rotation, a carrier tted with the other section and having a plurality of spaced radialslots, shiftable brushes-in the slots, and springs urging the brushes inwardly against the inner section to maintain an electrical connection between the sections.

2. A swivel joint for connecting two fluid con-v ducting'tubes comprising a tubular inner section to be secured to one tube, a tubular outer section to be secured to the other tube and surrounding the inner section. the outer section comprising a nipple to be secured to said other section and having an internal shoulder and a lcup shaped member whose open end portion is threaded onthe nipple, a bearing in said member connecting the sections for relative rotation,

tion the-lock ring 24 is removed. With the memthose skilled in the art or fall within the scope of the following claims:l

Having described my invention, I claim.:

1. A swivel Joint for connecting two fluid conducting tubes comprising a tubular 'inner section to be secured to one tube, a tubular outer `section to be secured to the other tube and surrounding the inner section, bearing means connecting the a spacer in said member between the inner side of the nipple and the bearing, s carrier held between the spacer and said shoulder, the side of the carrier which faces the spacer having radial slots,

and spring urged contact brushes in the slots engaging the inner section.

3. A swivel Jointl for connecting two iluid conducting tubes comprising a tubular inner section to be secured to one tube, a tubular outer section to be secured to the other tube and surrounding the inner section, the outer section comprising a nipple to be secured to said other section and having an internal shoulder and avcup shaped member whose open end portion is threaded on the nipple, a bearing in said member connecting the sections for relative rotation, a spacer in said member between the inner side ot the nipple and the bearing, a carrier held between the spacer and 'said shoulder, the side of the carrier winch faces the spacer having radial slots, spring urged contact brushes in the slots engsin the inner section, and sealing means in the. nipple at the other side of the carrier for sealing between the sections to prevent duid from reaching the brushes and bearing.

DWIGHT M. PHILLIPS. 

